The mere enablement of live presentation of information is well known in the art. An overhead foil projector, for example a 3M.RTM. Overhead Projector Model 213, provides a light source and lens to focus a beam of light on a screen in a room. By placing a transparent plastic foil or overhead "transparency" having textual or diagrammatic information over a holder, the information from the foil is readily available and readable by an audience from the screen. The presenter then manually selects and places a single transparent foil from a larger set of foils. This manual selection occurs until the last foil in the set has been displayed. The selection of foils may be dynamic with the presenter deciding to leave foils out of the presentation or skip sections of foils. The presenter typically speaks and interacts with the visual representation of each transparency on a screen.
Today, existing transparent plastic foils can be transformed into digital foils for use in a computer system. The textual and diagrammatic information is retained in the transformation process. It is also possible to create new and original digital foils directly in a computer system. Digital foils may also be supplemented with the addition of complex objects to include multimedia objects such as digital audio (voice, music, and sound effects), digital video, animation, and bitmap graphics (also known as multimedia components).
A portable computer coupled to a projection device, for example a PROXIMA.RTM. ColorWorks SX Model A502C True Color LCD projection panel, can deliver a digital foil presentation to a larger audience. A presentation panel simply diverts the contents of a display screen to another reception device like a screen on a wall in a conference room.
Improvements in computer memory, coupled with digital foil technology, can greatly increase the complexity (and usefulness) of foil presentations. A portable computer or notebook, for example the IBM.RTM. 750C ThinkPad.RTM., may be used to hold several hundred digital foils for use in a live presentation. A number of different modules and sections could make up many different presentations, making the task of presenting much larger and more complex.
Gaining and providing dynamic access, in a non-linear sense, to a large set of digital foils is difficult, and is further complicated where the digital foils have complex multimedia objects.
For the purpose of this application, it should be understood that the term `linear navigation" refers to sequential navigation permitting a single page up or down function. "Non-linear navigation" allows a presenter to redefine the presentation sequence of digital foils by permitting changes in flow between different modules, sections and units.
There are a number of problems associated with previous attempts at navigating digital foil presentations. Many software systems such as FreeLance.RTM., Harvard Graphics.RTM., and Slide Show from Asymetrix.RTM. Multimedia Toolbook provide a "screen show" capability which permits simple linear navigation between foils in a predefined sequence. The presenter cannot deviate from this sequence.
Other attempts provide popup dialog boxes which typically place a "table of contents" on a large portion of a display screen that is visible to the audience on the projection panel. This approach tends to distract the audience and disrupt the flow of the presentation. The presenter locates a pointer, either by keyboard command or by movement of a pointing device, over a symbol, word, or phrase in the table of contents to navigate to another display.
Hypertext and hypermedia systems also provide navigation with the placement of a pointer to activate a link. However, even lesser navigation distractions such as these are simply not acceptable for audience presentations because they typically take a great deal of time to operate accurately. This type of navigation system is more readily suited to a user privately viewing the content of a document and searching through unknown material.
In sharp contrast to a person searching for information, the presenter generally has in-depth knowledge of the substance of the presentation material and wants to scan quickly for a particular foil from a larger set of foils for greater flexibility during the act of presenting.